Process of sizing paper.



rnocnss or. SIZING PAPER.

, 1 Ho Drawing.

5 invented a new and useful Process for Sizing Paper, of which the following is a full, clear, and exact specification.

The treatment of paper in the course of itsmanufacture with slzelends" it strength, luster and, according to the mode of treatment, a certain impermeability to molsture, water, acids, gaws and the like.

.The treatment consists in adding a solution .of resin and salts of alumina to the paper pulp in the hollander; or the paper 15; treated with solutions of resin glue .or the like, andyfor the purpose of ing the latter, with solutions of alumimum sulfate, aluminium acetate, hydrated alumina, or the like, and ,,then dried. Soap solutions are generall whereby an insoluble alumina soap. is pre cipitated on the paper, so ,thatmore complete waterproofing is attained. Agaln, animal glue and casein are used, these adhesives being fixed by means of alums, chromates, formaldehyde or the like, whereby the paper becomes applicable for various purposes. By the present invention these several sizing and fixing agents are applied in the form of foam-baths; for example the bath is caused to foam by means of compressed air or other gas diffusing from porous bodies in the bath at any temperature. The foaming may be produced in any suitable vessel which contains the sizing or fixing liquid and has at its lower part one or more finely porous bodies, such as pipes or plates of burnt clay or graphite, through which the compressed air or other gas can be diffused in the liquid in such manner that foam is formed in the upper part of the container; .the paper. web to be sized is brought into contact on one or both sides with this foam by drawing the paper through the upper part of the vessel containing the, foam.

The following examples illustrate, the invention: 1

Example/I: The paper, either on the machine or after it'has left the machine, is

. brought into contact on one side, or is completely surrounded, with a resin size solu-,-

tion of the usual concentration which has Specification of Letters Patent.

7used as further fixing agents,

Patented J an. 2, 1917.

Application filed August 12, 1910. Serial No. 114,583.

been brought into the. condition of foam in the aforesaid manner. After partial or complete. drying, the paper is treated with a foam hath made in the "aforesaid manner from a-solution of aluminium sulfate of the usual strength for fixing the resin size and containing some saponin.

Example II: The paper, either on the machine or after it has left the machine is treated with foam produced in the aforesaid manner from a so ution of aluminium sulfate, of the usual concentration, containing some sa onin; after partial or complete drying t e paper is. then. treated with the foam from a soap-bath of the usual cona porous body into water containing saponin.

In both Example III and Example IV the treatment with the formaldehyde foambath may precede the treatment with glue,

casein or the like.

*Together with the foam-baths named above there may be applied to the. paper with advantage other materials necessary for waterproofing or softening it, such. as

caoutchouc, wax, paraflin-wax, glycerin or the like, since the foam bubbles are adapted to carry these materials emulsified in a very fine state of subdivision and to dis-- tribute them on the paper uniformly owing to the constant movement of the bubbles.

For instance, to the aluminium sulfate solution used in Example I may be added more orless of a solution of 1.5 kilos of caoutchouc, ceresin or parafiin-wax and 1.25 kilos of glycerin in a mixture of 2 kilos of oil of turpentine and 4 kilos of strong alcohol.

The invention permits of obtaining uniform sizingwith a considerably smaller amount of chemicals and smaller baths than hitherto usual, since the foam bubbles satunemeee rate the paper mass uniformly. Moreover, the easily torn paper webs are essentially preserved andwaste reduced.

What I claim is: b 1. A process for sizing paper whereinthe sizing and fixing baths are applied to the aper mass or the paper, in the form of 0am, substantially as described,

2. A process for sizing paper wherein w there "is applied to paper which has been treated with glue, casein or the like, a fixing DR. RENE CLAVEL,

Witnesses Annow Znemn, AMAND RR, 

